Amplifier



FIG. 1 is a perspective view of an amplifier, showing my new design;

FIG. 2 is a top view thereof;

FIG. 3 is a front view thereof;

FIG. 4 is a right-side view thereof;

FIG. 5 is a rear view thereof;

FIG. 6 is a left-side view thereof; and,

FIG. 7 is a bottom view thereof.

The broken lines show unclaimed subject matter only and do not for anypart of the claimed design.

CLAIM The ornamental design for an amplifier, as shown and described.